Senator was British but not foreign, says Roberts's lawyer

ONE Nation senator Malcolm Roberts's lawyer has told the High Court his client was a "natural-born Indian”, but that was just a distraction from the real citizenship case against him.

Barrister Robert Newlinds SC began his case yesterday by declaring Sen Roberts was never a dual citizen and the key arguments against him were "wrong and irrelevant”.

He declared Sen Roberts was an Australian citizen as soon as he arrived in the country because it was still part of the British Empire at the time.

The fact he was born in India was not relevant and nor was the fact he was not a "natural-born Australian”.

Britain wasn't a "foreign power” at that stage, he said.

Subjects could move freely between the colonies and choose where they wanted to live. He argued they then became a national of that country while also being a British subject.

It was only relevant that Sen Roberts's father was Welsh.

Mr Newlinds also said the Australian citizenship documents his client signed in 1974 were "not a big deal” as they did not give him any rights or duties - such as voting or conscription - he didn't already have.

He also rejected the government's argument that by doing nothing to renounce his British citizenship, Sen Roberts voluntarily retained it.

Mr Newlinds also said Deputy Prime Minister Barnaby Joyce was in "the same boat” as Sen Roberts as the same arguments could apply to his father, who came to Australia from New Zealand, which was also part of the British Empire at the time.

Mr Newlinds also argued the Senator's state of mind was a significant factor - his belief from 1974 was that he was only an Australian.

After a cross examination hearing last month, the High Court found the Queensland senator was a British citizen at the time he signed his senate nomination form and that he knew it.

Earlier yesterday, the court heard Deputy Nationals leader Fiona Nash should lose her seat because she was a British citizen at the time of her nomination.

Geoffrey Kennett SC, who as "friend of the court” provides information but is not related to any case, also advised the court Nationals senator Matt Canavan should be disqualified.

"There appears to be no doubt at the time of her nomination Senator Nash was a British citizen and on our instructions that should be the end of the matter,” Mr Kennett said.

In Sen Canavan's case, he said the revelation the Senator might not actually be Italian after all, revealed by his lawyer on Monday, required the court to find that a point of Italian law was unconstitutional.

There were major problems with that, he said.

Sen Nick Xenophon's case was more complicated given he had an obscure form of British citizenship, he said.

It was the final day of hearings for the dual citizenship cases of seven federal MPs.

Mr Joyce and his Nationals colleagues Fiona Nash and Matt Canavan have all argued they should be spared the court's wrath. So has crossbencher Mr Xenophon.

But the lawyer for Greens former senators Scott Ludlam and Larissa Waters says they were right to resign, and argued the other five should follow suit.